What are Australian dunes?

Australian dunes are sand formations found in deserts, along coastlines, and on lake margins across the country. They range from the long parallel red dunes of the Simpson Desert to the towering white quartz dunes of Fraser Island (K'gari) and the eroded coastal dunes of the New South Wales central coast.

Inland sand dunes cover about 40 per cent of Australia, especially in the Simpson, Strzelecki, Great Sandy, Tanami, and Great Victoria deserts. The Simpson Desert holds the world's largest dune field, with about 1,100 parallel red dunes running for hundreds of kilometres, formed and reorganised by prevailing south-easterly winds during the Quaternary period. Dune colour comes from iron-oxide coatings on quartz grains, the same process that gives the Outback its red colours.

Coastal dunes line about 35 per cent of the Australian coastline. The world's three largest sand islands are all in south-east Queensland: Fraser Island (K'gari) at 1,840 square kilometres, Moreton Island, and North Stradbroke Island, all built from sand transported north by the East Australian Current over hundreds of thousands of years. Fraser Island was inscribed on the UNESCO World Heritage List in 1992 and is the only place where tall rainforest grows directly on sand.

Dunes elsewhere include the high coastal dunes of Eyre Peninsula and the Great Australian Bight, the Snowy Mountains lunette dunes of inland New South Wales, and lake-shore lunettes such as those at Lake Mungo in the Willandra Lakes World Heritage Area, which preserve evidence of human occupation back at least 50,000 years. Dunes face pressure from invasive weeds (especially bitou bush along the New South Wales coast), four-wheel-drive damage, and rising sea levels eroding coastal sands.